TY - JOUR
T1 - Evolution of flow characteristics through finite-sized wind farms and influence of turbine arrangement
AU - Sharma, V.
AU - Cortina, G.
AU - Margairaz, F.
AU - Parlange, M. B.
AU - Calaf, M.
PY - 2018/1/1
Y1 - 2018/1/1
N2 - Evolution of flow characteristics through finite-sized wind farms and the influence of the wind-farm configuration on modulating this evolution is explored through numerical simulations. The principal aim for the study is to identify regions of flow-adjustment and flow equilibrium within the wind farm. Towards this aim, a suite of five large-eddy simulations (LES) of the neutral atmospheric boundary layer with extremely long streamwise domains are performed with embedded finite-sized wind farms of different streamwise and spanwise spacing. Three diagnostic variables, namely, the wind-farm induced effective surface roughness, the wake viscosity and the wake-expansion coefficient are computed using the LES-generated database and are used to characterize the flow. Computation of the diagnostic variables is relevant to the wind-energy community in different contexts ranging from parametrization of wind farms in weather and climate models, to wind-farm design and optimization based on wake-models and eddy-viscosity type Reynolds-averaged Navier-Stokes solvers. Results show that flow equilibrium is achieved in the ‘most dense’ configuration of sx≈8D,sy≈5D at approximately the 19th row. Results also indicate that the streamwise spacing plays a dominant role determining the rate at which flow-adjustment is achieved within the wind farm.
AB - Evolution of flow characteristics through finite-sized wind farms and the influence of the wind-farm configuration on modulating this evolution is explored through numerical simulations. The principal aim for the study is to identify regions of flow-adjustment and flow equilibrium within the wind farm. Towards this aim, a suite of five large-eddy simulations (LES) of the neutral atmospheric boundary layer with extremely long streamwise domains are performed with embedded finite-sized wind farms of different streamwise and spanwise spacing. Three diagnostic variables, namely, the wind-farm induced effective surface roughness, the wake viscosity and the wake-expansion coefficient are computed using the LES-generated database and are used to characterize the flow. Computation of the diagnostic variables is relevant to the wind-energy community in different contexts ranging from parametrization of wind farms in weather and climate models, to wind-farm design and optimization based on wake-models and eddy-viscosity type Reynolds-averaged Navier-Stokes solvers. Results show that flow equilibrium is achieved in the ‘most dense’ configuration of sx≈8D,sy≈5D at approximately the 19th row. Results also indicate that the streamwise spacing plays a dominant role determining the rate at which flow-adjustment is achieved within the wind farm.
KW - ABL-wind farm interaction
KW - Effective roughness
KW - Large-eddy simulation
KW - Wake viscosity
KW - Wake-expansion coefficients
UR - http://www.scopus.com/inward/record.url?scp=85029683633&partnerID=8YFLogxK
U2 - 10.1016/j.renene.2017.08.075
DO - 10.1016/j.renene.2017.08.075
M3 - Article
AN - SCOPUS:85029683633
VL - 115
SP - 1196
EP - 1208
JO - Renewable Energy
JF - Renewable Energy
SN - 0960-1481
ER -